PAK1 Knockout Cell Lysate

Severe acute pancreatitis (SAP) is a condition associated with high rates of mortality and lengthy hospital stays. In the current study, SAP mouse models were established in BALB/c wild-type and P21-activated kinase 1 (PAK1) knockdown mice with the objective of determining the expression of microRNA-542-5p (miR-542-5p) and the subsequent elucidation of the mechanism by which it influences acute lung injury (ALI) by mediating mitogen-activated protein kinase (MAPK) signaling and binding to PAK1. The targeting relationship between miR-542-5p and PAK1 was verified using the bioinformatics prediction website and by the means of a dual-luciferase reporter assay. Following the SAP model establishment, the mice were assigned into various groups with the introduction of different mimic and inhibitors in an attempt to investigate the effects involved with miR-542-5p on inflammatory reactions among mice with SAP-associated ALI. Our results indicated that PAK1 was targeted and negatively mediated by miR-542-5p. Mice with SAP-associated ALI exhibited an increased wet-to-dry weight ratio, myeloperoxidase activity, serum amylase activity, TNF-alpha, interleukin-1 beta (IL-1 beta), and intercellular adhesion molecule-1 (ICAM-1) contents, p-p38MAPK, p-ERK1/2, and p-JNK protein levels as well as PAK1 positive expression, while decreased miR-542-5p levels were observed. Functionally, overexpression of miR-542-5p improves ALI in mice with SAP via inhibition of the MAPK signaling pathway by binding to PAK1.Based on the evidence from experimental models, miR-542-5p was shown to improve ALI among mice with SAP, while suggesting that the effect may be related to the inactivation of the MAPK signaling pathway and downregulation of PAK1 gene. Thus, miR-542-5p could serve as a promising target for ALI treatment.

Acute myeloid leukemia (AML) is a genetically heterogeneous group of oncological diseases of the hematopoietic system, which are extremely difficult to treat. The development of new targeted drugs (Hylteritinib, Venetoclax) significantly improved the survival of patients, but resistance, as well as cytotoxic anti-leukemia drugs, often occurs. The search for new molecular targets for the development of effective approaches for the treatment of AML is very urgent. In blast cells of patients with AML, mutations, chromosomal rearrangements, and increased expression of a number of non-mutant genes, including transcription factor genes, are detected. The transcription factor Sp1 binds to GC-rich regions of regulatory regions of various genes and thus controls their expression. Sp1 targets include genes responsible for proliferation, cell cycle regulation, and differentiation. In many malignant diseases, a high level ofSp1gene expression is associated with an unfavorable prognosis, therefore, Sp1 is considered as a promising therapeutic target for cancer. In this paper, we estimated the expression levels ofSp1in various malignant tissues. IncreasedSp1expression was detected in samples obtained from patients with AML, acute lymphoblastic leukemia, Ewing sarcoma, ovarian and kidney cancer. It is also shown thatSp1expression correlates with the expression of genes encoding cytokine receptors and growth factors (CSF1R and IL6R), intracellular kinases (CSK, SYK, PAK1, ILK, JAK2), and transcription factor LMO2. The correlation between expression levels ofSp1andCSF1R,SYK,Jak2andLMO2is also characteristic of transplanted human leukemia cells. We measured expression levels ofSp1,CSF1R,ILK,PAK1in the cells of three transplantable lines of human leukemia and found increased levels of expression of these genes in Kasumi-1 cells. In addition, we showed that Kasumi-1 cells are most sensitive to Mitramycin, a drug that displaces Sp1 from its targets with DNA. Our data indicate the need to identify AML cells that are most sensitive to inhibition of Sp1 activity in order to assess the possibility of suppressing its activity in vivo.